Turbo exhaust
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Turbo exhaust How much power is their to gain with a catback from stock to aftermarket for a turboed car????
want to keep it as quiet as possible....
hp/tq numbers would be nice, estimates anyway...
hope u guys can lead me in the right direction.
want to keep it as quiet as possible....
hp/tq numbers would be nice, estimates anyway...
hope u guys can lead me in the right direction.
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I would run some magnaflow straight thru oval mufflers.
The same type of muffler sounds completely different on turbo cars.
The turbine wheel is a restriction in the exhaust flow.. One that makes power but it also soaks up some of the noise. Ever hear a typical honda with a straight thru catback vs a turbo DSM with one?
The same type of muffler sounds completely different on turbo cars.
The turbine wheel is a restriction in the exhaust flow.. One that makes power but it also soaks up some of the noise. Ever hear a typical honda with a straight thru catback vs a turbo DSM with one?
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Just run a good super low restriction turbo back...
You dont want to open the really fing lound cutout just to see how much sooner it would have spooled with a better full system..
Two straight thru magnaflows + the turbo = much quieter than a NT Ls1 with magnaflows.
You dont want to open the really fing lound cutout just to see how much sooner it would have spooled with a better full system..
Two straight thru magnaflows + the turbo = much quieter than a NT Ls1 with magnaflows.
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A turbo car is more sensitive to backpressure than a supercharged one. You see, the turbine side runs at a pressure ratio of, say, 3 to 1. So, any time you add 1 psi to the exit side, the intlet side has to increase 3 psi for the turbine to produce the same amount of compressor drive power. So, even though you think your stock muffler is only adding 3 psi backpressure, it's really adding 9 psi at the motor. Furthermore, a free flowing exhaust after the turbine will reduce spool time.
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Originally Posted by Jaegermeister2k
Wouldn't an SLP loudmouth be perfect for a turbo fbody?
That's what I'm doing.
As far as a 400rwhp-500rwhp street application, any backpressure issues because of a free-flowing exhaust vs. a more restrictive one will never be felt SOTP, very little impact. Just get the exhaust whose sound you like, and very easily set the boost controller at whatever power level you like when you tune it. It's that simple. I happen to like it loud. That's just me. When you pick an exhaust, keep in mind that it will be slightly quiter with a turbo and then make your pick. Just my $0.02
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Originally Posted by bboyferal
As far as a 400rwhp-500rwhp street application, any backpressure issues because of a free-flowing exhaust vs. a more restrictive one will never be felt SOTP, very little impact.
I beleve what he meant is that those extra 40-100 rwhp aren't going to push you in the seat like a 40-100 h[p nitrous shot would. But instead would add up gradually and add 40-100 hp in the peak. SO it won't be SOTP like he said. But i'm sure you can feel it. BTW. If you gained 100 hp in a 500 hp car by reducing backpressure you must've gone from like a flowmaster with 2 stock cats to open downpipe or something. Cause i can't imagine many mufflers that are that restrictive. 
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Originally Posted by Jaegermeister2k
But instead would add up gradually and add 40-100 hp in the peak.
Originally Posted by Jaegermeister2k
If you gained 100 hp in a 500 hp car by reducing backpressure you must've gone from like a flowmaster with 2 stock cats to open downpipe or something. Cause i can't imagine many mufflers that are that restrictive.
Originally Posted by Jaegermeister2k
I beleve what he meant is that those extra 40-100 rwhp aren't going to push you in the seat like a 40-100 h[p nitrous shot would. But instead would add up gradually and add 40-100 hp in the peak. SO it won't be SOTP like he said. But i'm sure you can feel it. BTW. If you gained 100 hp in a 500 hp car by reducing backpressure you must've gone from like a flowmaster with 2 stock cats to open downpipe or something. Cause i can't imagine many mufflers that are that restrictive.
That's what I meant! I will run whatever exhaust I like the sound of. If I'm short 10 rwhp, I'll fiddle with the boost controller. I doubt it will even be that much. We are not talking about cars with the header collectors open, here. I thought we might be discussing cat-backs.
With so many harsh criticisms of the loudmouth with NA applications once these guys do ORY and headers concerning sound, it almost seems like a turbo set-up would be it's best duty. I will have the PTK tubing all the way to the Loudmouth. I think that is pretty free-flowing as it can get, too.
For the original poster, it might be too loud. Libertine on this board can tell you exactly about this set-up. He runs a TTI race kit w/ Loudmouth. He describes the sound like Maximus from Gladiator, "...at my signal, unleash hell!" when he guns it. Definitely not quiet.
Last edited by bboyferal; Sep 18, 2005 at 07:43 PM.
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Originally Posted by engineermike
A turbo car is more sensitive to backpressure than a supercharged one. You see, the turbine side runs at a pressure ratio of, say, 3 to 1. So, any time you add 1 psi to the exit side, the intlet side has to increase 3 psi for the turbine to produce the same amount of compressor drive power. So, even though you think your stock muffler is only adding 3 psi backpressure, it's really adding 9 psi at the motor. Furthermore, a free flowing exhaust after the turbine will reduce spool time.
Originally Posted by bboyferal
Thank you. That's what I meant!
For the original poster, it might be too loud. Libertine on this board can tell you exactly about this set-up. He runs a TTI race kit w/ Loudmouth. He describes the sound like Maximus from Gladiator, "...at my signal, unleash hell!" when he guns it. Definitely not quiet.
That's what I meant! For the original poster, it might be too loud. Libertine on this board can tell you exactly about this set-up. He runs a TTI race kit w/ Loudmouth. He describes the sound like Maximus from Gladiator, "...at my signal, unleash hell!" when he guns it. Definitely not quiet.
The typical honda sounds like a bumble bee where as my turbo car does'nt...
Its deep with no "bzzz" at all at idle and cruise. When you dip into the boost it has a deep loud roar. Their is a wide dynamic range on this engine. Sips fuel and air at an idle or cruise but consumes enough of both for high 6xxhp at wot. So basically a turbo car will be quieter off the boost cruising or sitting but be much louder when boosting...
FWIW I think the 4" system is a good idea.
I am thinking about a 4" dual system on the project car.
Last edited by V8_DSM_V8again; Sep 18, 2005 at 11:35 PM.
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Before I raised the idle speed it used to lope like a NA car with a big cam..
The dynamic range of really high powered 4's makes it hard to get a good idle sometimes.
You need an amount of fuel at idle the same as a stock or even non turbo 2.0 but at full tilt you need enough for 600+ hp and have to get it from 4 injectors.
At the stock idle rpm (750 warm) the injectors try to run between 1-2 milliseconds. The fuel flow at those really short open times is'nt consistant. On cooler days it would idle better because of more milliseconds of duty. The 4.75lb SSG flywheel made the lope worse because the RPMs could change quicker. I raised idle to about 1,000 rpm...
The dynamic range of really high powered 4's makes it hard to get a good idle sometimes.
You need an amount of fuel at idle the same as a stock or even non turbo 2.0 but at full tilt you need enough for 600+ hp and have to get it from 4 injectors.
At the stock idle rpm (750 warm) the injectors try to run between 1-2 milliseconds. The fuel flow at those really short open times is'nt consistant. On cooler days it would idle better because of more milliseconds of duty. The 4.75lb SSG flywheel made the lope worse because the RPMs could change quicker. I raised idle to about 1,000 rpm...
